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| author | Ben Gardon <bgardon@google.com> | 2021-02-02 10:57:21 -0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2021-02-04 05:27:41 -0500 |
| commit | 0f99ee2c7a58fc281c084d3acc0f0013bec7ec5a (patch) | |
| tree | 6100d8999ff841beb77ef0235c010e0c01528ba0 /arch/x86/kvm | |
| parent | 1af4a96025b33587ca953c7ef12a1b20c6e70412 (diff) | |
| download | linux-0f99ee2c7a58fc281c084d3acc0f0013bec7ec5a.tar.bz2 | |
KVM: x86/mmu: Skip no-op changes in TDP MMU functions
Skip setting SPTEs if no change is expected.
Reviewed-by: Peter Feiner <pfeiner@google.com>
Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20210202185734.1680553-16-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm')
| -rw-r--r-- | arch/x86/kvm/mmu/tdp_mmu.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c index c8a1149cb229..aeb05f626b55 100644 --- a/arch/x86/kvm/mmu/tdp_mmu.c +++ b/arch/x86/kvm/mmu/tdp_mmu.c @@ -888,7 +888,8 @@ static bool wrprot_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root, continue; if (!is_shadow_present_pte(iter.old_spte) || - !is_last_spte(iter.old_spte, iter.level)) + !is_last_spte(iter.old_spte, iter.level) || + !(iter.old_spte & PT_WRITABLE_MASK)) continue; new_spte = iter.old_spte & ~PT_WRITABLE_MASK; @@ -1065,7 +1066,8 @@ static bool set_dirty_gfn_range(struct kvm *kvm, struct kvm_mmu_page *root, if (tdp_mmu_iter_cond_resched(kvm, &iter, false)) continue; - if (!is_shadow_present_pte(iter.old_spte)) + if (!is_shadow_present_pte(iter.old_spte) || + iter.old_spte & shadow_dirty_mask) continue; new_spte = iter.old_spte | shadow_dirty_mask; |